(MK2S) Problem with initial layer - left side too squished, right side too far up
Whenever I print with my MK2S, the left hand side is too squished, and the right hand side is not squished enough and sometimes barely sticks to the build plate. I've had my kit MK2S for almost a year, and I've never been able to resolve this issue. I can usually print small items at the center of the plate, but I can never successfully print anything that takes up the whole bed without severely elephant footing the left side. It's been driving me nuts, because with time it's somehow gotten worse over time and I haven't been able to fix it. I've done my due diligence and poured over the build manual and these forums, and have had no luck fixing my issue with what I've found. I've done the following to fix it , and nothing has worked:
[*] Use the bed correction - 50 microns only gets me to "almost there, just a little bit more..."
[*] Ensure I'm at the latest firmware - Using 3.1.0 with an SD card and the latest version of Prusa Slic3r.
[*] Push the Y-axis fully into the frame.
[*] Ensure every belt is the correct tension.
[*] Made sure the PINDA probe is at the correct height.
[*] Ensuring my bed is as clean as possible.
[*] Do everything without the spool resting on the frame.
[*] Change out the top Z-brackets for geometrically corrected ones ( https://www.thingiverse.com/thing:2552246 )
[*] Make sure the Y-axis smooth rods are fully inserted into their place.
[*] Ensure the frame alignment is absolutely perfect - its taken me many hours of tweaking to get that "Good Job!"
Some time in May of last year, I had to replace my buildplate, as I accidentally broke it trying to remove a print. I never noticed it with original build plate from the kit, as I primarily printed with PLA at the time. The issue is worse with PETG, as it is sensitive to an unlevel bed. I've mostly noticed this issue with my second bed, when I got serious about mostly printing in PETG. In my entire time in trying to diagnose this issue, I've notice something odd about the Y axis and its relation to the frame. If I move the buildplate forward and align the rear screws that hold the build plate to the carriage with the frame, it seems like not only is the left side actually higher than the right side, but the screws seem... off from where one would think they would be. Please take a look at the attached pictures as they hopefully show the issue better than I can explain it. I've also tried to "trick" the printer into fixing this, by raising the right hand side of the print up from the frame, but the printer does the same thing over and over again.
This has driven me absolutely nuts and I have no idea how to fix it. What's wrong with my printer? what can I do to fix it? What have I missed?
Re: (MK2S) Problem with initial layer - left side too squished, right side too far up
Check that the 'high' side threaded rod is correctly seated in the frame. Correcting that would tilt the bed back to level.
Bill
Tagaytay City, Philippines
Founder member of Philippines Prusa Printer Owners FB Group
Sponsor Pillars of God Academy in Bacoor
Re: (MK2S) Problem with initial layer - left side too squished, right side too far up
I already tried that. What you see is when both sides are fully pushed into the frame.
Re: (MK2S) Problem with initial layer - left side too squished, right side too far up
Next thing that comes to mind. Please check the seating of your y-axis smooth rods at each of the four corners.
Bill
Tagaytay City, Philippines
Founder member of Philippines Prusa Printer Owners FB Group
Sponsor Pillars of God Academy in Bacoor
Re: (MK2S) Problem with initial layer - left side too squished, right side too far up
You said bed correction is 50 microns. Isn't hyperfine adjustment -99/+99?
Re: (MK2S) Problem with initial layer - left side too squished, right side too far up
Just wanted to close up this thread. I ended up fixing the issue by adding washers (from the spares bag of the printer kit) to the top right and bottom right corners of the bed in order to raise it up just enough for the auto leveling to be useful. I made this model ( https://www.thingiverse.com/thing:2838514 ) to test if this worked before and after. I don't have any pictures unfortunately, but before, I was literally only able to successfully complete the left half of those squares. After adding the washers and redoing the z-leveling procedure, I reprinted the squares and was able to successfully print all of the squares. Another thing I noticed is that while printing PETG (my main filament of choice and why my bed needs to be absolutely level), I was using the wrong bed temperature. I assumed the pre-configured profile in Prusa Slic3r had the bed too hot, as PET usually needs a hotter bed temperature than PETG. I was normally printing PETG using a bed temperature of about 50C, as a lot of places and even the boxes of some filaments suggest similar settings to PLA with regard to substrate preparation. However, the profile is meant as a general profile for all PETs - PET-E, PET-G, PET-T, etc. Running this profile (meaning the bed running at about 80-90C) and redoing the z-live level showed the filament sticking REALLY well to the bed regardless of part location on the bed. Everywhere on the bed I now get a perfect first layer and my prints complete successfully. Removal of the item from the bed, even after using blue glass cleaner between prints and waiting for the bed to cool, is now a different problem... some of the items stick WAY too well! I would consider my issue completely fixed. I don't know who said it on this forum, but someone once said that you don't ever mess with a fully working 3D printer - I'm not going to try to do anything to remove those washers and am content with the printer and the way it works for now. Hopefully this helps someone else with this issue.
Edit - to respond to the other people on this thread - I took calipers to everything and pretty much rebuilt my machine twice (before and after this post) - it was all definitely to spec and was still getting that weird issue. Not a rod or screw out of place. I used this infamous image to get everything just right: 
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